Device for stopping the films in cinematograph projection apparatus



Dec. 4 1923. 1,476;O87

s. KUCHARSKI DEVICE FOR STOPPING THE FILMS IN CINEMATOGRAPH PROJECTION APPARATUS Filed Aug. 51, 1921 IAMEIJTU m2 a TT'E| N as v die,

Patented Dec. 4, 1923.

I UNITED STATES. PATENT OFFICE.'

STANISLAUS KUCHARSKI, OF CHAR-LOTTENBURG, NEAR BERLIN, GERMANY.

DEVICE FOR STOPPING THE FILMS IN CINEMATOGRAPH PROJECTION APPARATUS.

Application filed. August 31, 1921. Serial No. 497,302.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 41 STAT. L, 1313.)

To all whom it may concern."

Be it known that I, STANISLAUS KUCHAR- sin, a citizen of Germany, residing at Charlottenburg, near Berlin Dernburg-Strasse 45, have invented certain new and useful Im-.

rovements in a Device for Stoppin the l ilms in Cinematograph Projection pparatus (for which I have filed applications in Germany January 28, 1920; Great Britain June 8, 1820), of which the following is a specification.

The invention relates to a device in cinematograph projection apparatus for stop ping the film in a position in which an image in the film window is illuminated, so that on account of the longer time during which the film is stationary, explanations can be given or any required adjustments can be made. The devices known for this purpose have comparatively complicated parts to ensure the stopping of the film in the position in which it is not covered by the shutter, but in which the image is projected on to the screen. The invention attains this result by .very simple means in which a spring is moved into the path of a projection rotating with gear driving the film, the spring is tensioned by the momentum of the parts associated with the stop and after the momentum has been' exhausted these parts are again returned by the spring into a position in which the image in the window is illumi nat'ed.

An example of a construction according to the invention is shown in Fig. 1 of the accompanying drawing in elevation Fig. 2 shows a front view of the disc carrying the projection.

Connected with, for example, the driving gear actuated by a suitable motor for feedmg the film, there is a disc at which carries a projection b. This projection is on a lever c mounted on the disc and by'the momentum of its heavy end d and a spring e engaging with its other end, tends during the rotation of the disc a to approach the axis of the disc. I

Opposite the disc a there is a lever g pivoted on an axle f carrying a cylindrical box It in which a helical spring 2' is wound 'which is fastened at one end is in the box, while its other end Z projects externally and is provided with a hook m.

the armature of which is formed During the normal drive the lever g with the box it rests against a stop a, so that the spring end Z is outside the path of the disc a and of the projection 12. When the film is to be stopped the circuit of an elec-tromagnet o, by the lever g, is closed. by a switch of suitable type. The lever g is thereby attracted and the spring end Zcomes into the path of the projection b. This projection which rotates with the disc at in the direction of the arrow shown in Fig. 2 slips over the. spring end Z and engages in the hook m. In consequence of its momentum, the drive is continued and the projection b winds up and tensions the spring 71 to a certain extent. When the momentum of the drive is exhausted, the spring is de-tensioned and brings the drive back by means of the projection 6 into the position which correspondsto the de-tensioned con dition of the spring. This is, however, a position in which the film stands in the window with a fully illuminated image; The correct position of the film is, therefore,

secured by a simple tensioning and de-tensioning of the spring.

The arrangement can also be such that the spring is on the rotating part and the projection on the nonrotating part.

I claim:

' In cinematograph apparatus, the combination with the film moving mechanism, of means for insuring the proper positioning of a picture at the projection opening when the movement of the film is stopped, said means being normally inoperative, and means for movin the same into operative position, said a wheel driven by the film moving means, a stop in connection with the Wheel and centri ugally controlled to inoperative position by the movement of the wheel, and a spring controlled brake mechanism for engagement by the stop, normally out of engaging position when the stop is in operative position.

In testimony whereof I have afiixed my signature in presence of two witnesses.

ALWIN HAUsmNN, GUSTAV Pm'rson.

positioning means comprising 

